The French prosecutor investigating the shooting of a British couple and two others in the Alps has said all those killed were shot twice in the head, as police officers searched the UK home of victim Saad al-Hilli.

Police have begun searching the home of French shooting victim Saad al-Hilli in Claygate, Surrey (Picture: PA)

Eric Maillaud said that post-mortem tests confirmed that al-Hilli, his wife and the two other victims were shot twice in the head, but declined to give any further details.

He also revealed that police in neighbouring Switzerland and Italy would be joining the ongoing investigation.

Mr Millaud had previously revealed investigators were looking into the possibility that Mr al-Hilli and his brother had been arguing over money in the run-up to the deaths.